FFmpeg
bswap.h
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #ifndef AVUTIL_RISCV_BSWAP_H
20 #define AVUTIL_RISCV_BSWAP_H
21 
22 #include <stdint.h>
23 #include "config.h"
24 #include "libavutil/attributes.h"
25 #include "libavutil/riscv/cpu.h"
26 
27 #if defined (__GNUC__) || defined (__clang__)
28 #define av_bswap16 __builtin_bswap16
29 
30 static av_always_inline av_const uint32_t av_bswap32_rv(uint32_t x)
31 {
32 #if HAVE_RV && !defined(__riscv_zbb)
33  if (!__builtin_constant_p(x) &&
34  __builtin_expect(ff_rv_zbb_support(), 1)) {
35  uintptr_t y;
36 
37  __asm__ (
38  ".option push\n"
39  ".option arch, +zbb\n"
40  "rev8 %0, %1\n"
41  ".option pop" : "=r" (y) : "r" (x));
42  return y >> (__riscv_xlen - 32);
43  }
44 #endif
45  return __builtin_bswap32(x);
46 }
47 #define av_bswap32 av_bswap32_rv
48 
49 #if __riscv_xlen >= 64
50 static av_always_inline av_const uint64_t av_bswap64_rv(uint64_t x)
51 {
52 #if HAVE_RV && !defined(__riscv_zbb)
53  if (!__builtin_constant_p(x) &&
54  __builtin_expect(ff_rv_zbb_support(), 1)) {
55  uintptr_t y;
56 
57  __asm__ (
58  ".option push\n"
59  ".option arch, +zbb\n"
60  "rev8 %0, %1\n"
61  ".option pop" : "=r" (y) : "r" (x));
62  return y >> (__riscv_xlen - 64);
63  }
64 #endif
65  return __builtin_bswap64(x);
66 }
67 #define av_bswap64 av_bswap64_rv
68 #endif
69 
70 #endif
71 
72 #endif /* AVUTIL_RISCV_BSWAP_H */
av_bswap32_rv
static av_always_inline av_const uint32_t av_bswap32_rv(uint32_t x)
Definition: bswap.h:30
av_const
#define av_const
Definition: attributes.h:84
ff_rv_zbb_support
static av_const bool ff_rv_zbb_support(void)
Definition: cpu.h:34
cpu.h
attributes.h
av_always_inline
#define av_always_inline
Definition: attributes.h:49
__asm__
__asm__(".macro parse_r var r\n\t" "\\var = -1\n\t" _IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31) ".iflt \\var\n\t" ".error \"Unable to parse register name \\r\"\n\t" ".endif\n\t" ".endm")